Today, safety is a priority in food and dairy industry and an important step for introducing the traditional products for industrial production.

Determination of antimicrobialactivity and evaluation of the safety of candidatestrains based on antibiotics susceptibility and virulence potential genes are the most important safety assessment steps. The ability to inhibit other bacteria may allow the probioticto inhabit a niche; and increase its ability to competitivelyinhibit other gastrointestinal microbes and pathogenicbacteria. Moreover, antimicrobial activity may control fermentation and increase the shelf life of foodproducts. Purified antimicrobial compounds can be used as additives, but In situ production of antimicrobialcompounds using a producer starter culture is regarded as amore commercially attractive strategy in fermented food.

This study aimed toevaluate the safety and antimicrobial potential of Lactobacillus pentosus22C, isolated from traditional yogurt fromKermanshah province, Iran. Strain 22C showed no undesirableamino acid decarboxylase and β-hemolytic activities. The isolate was assessed for the incidence of virulence genes (gelE, efaAfm, efaAfs, ace, espfs, cylM, cylA and cylB), sensitivity to various antibiotics and virulence phenotypes. The strain produced an antimicrobial molecule named pentocin22C, a small peptide with a relative mass between 5 and 10 kDa. Bacterial inhibition was pH-independent, with greater activity at pH 4-6. Purified or semipurified antimicrobialagents can be used as bio-preservatives, and theproducing strain can be used as a Bacteriocin producing starter culture to improve food safety.